Guanidine phosphate fertilizer



Patented Feb. 16, 1937 UNITED STATES PA TEN'fEl oFFicE' 2,070,581 a GUANIDINE rnosrmrrn mn'rimznn Harry A. Curtis, Knoxville, Tenn.', assignor to Tennessee Valley Authority, Wilson Dam, Ala.,

a corporation No Drawing. Application August 23,1935, Serial I 6 Claims. (CI. 71-29) I (Granted under the act of March 3, 1883, as amended April so, 1928; 370 o. G. 757) This application is madeunder the act of March 3, 1 3 as amended April 30, 1928, and the inven on herein described, if patented, may be manufactured and used by or for the Govern- 5 ment for governmental purposes without the payment to me of any royalty thereon.

This invention relates to fertilizer compositions and particularly those which contain a guanidine salt as an essential constituent.

One of the objects of this invention is toiprovide an improved superphosphate containing more than one element essential as a plant food. Another object of this invention is to provide a composition which contains both inorganic and or- I game nitrogen. Still another object of this'invention is to provide a fertilizer composition in which the constituent which contains the organic nitrogen is derived from an economical source not hitherto made extensively available for fertilizer use. Another object of this invention is to provide a fertlizer which contains a substantial pro portion of water-soluble organic nitrogen. Other objects of this invention include the provision for a fertilizer composition which contains a high percentage of organic nitrogen.

I have produced a new and improved superphosphate fertilizer which contains nitrogen as an essential element in the form of a guanidine salt.

One example for the production of the improved fertilizer composition which lies within the scope of this invention is given as follows: A triple superphosphate, which is essentially mono-calcium phosphate, is treatedwith a nitrifying composition which contains approximately 23% by 1 weight of ammonia and 27% by weight of guani-' dine, so that the ratio of the-inorganic nitrogen to the organic nitrogen is 1 to 1. The principal constituents of the resulting product are monocalcium phosphate, di-calcium phosphate, mono-i ammonium phosphate and (ii-ammonium phosphate, and guanidine phosphate.

A second example for the production of the improved fertilizer composition is given below: A

triple superphosphate is treated with a nitrifying solution which contains approximately 37% by weight of ammonia and 13% by weight of triguanidine phosphate, so that the ratio of the inorganic nitrogen to the organic nitrogen is 5: 1.

The principal constituents of the resulting product are mono-calcium phosphate, di-calcium phosphate, mono-ammonium phosphate, di-ammonium phosphate and guanidine phosphate.

A third example for the production of this improved fertilizer composition follows: A triple 5 superphosphate is treated with 'a liquid mixture of a solution containing approximately 40% by weight of free ammonia and 10% by weight of di-guanidine sulfate, together with calcium sulfate in suspension. The principal constituents of 10 the resulting product are mono-calcium phosphate, di-calcium phosphate, mono-ammonium phosphate, di-ammonium phosphate, guanidine phosphate and calcium sulfate.

It is evident that here are numerous factors 15 which will influence conditions for the most satisfactory production and use of the .compositions covered by this invention, the actual limits of which cannot be established except by detailed study of each set of raw materials and finished 20 products involved. The superphosphate, which is nitrifled, may be of the character normally usedfor ammoniation with aqueous or anhydrous ammonia and other nitrifying compositions. The finished fertilizer composition maycontaina va- 25 rlety of constituents, depending upon the nature of the superphosphate used and the'speciflc na- When a liquid nitrifying composition, which contains a solution of guanidine sulfate, is used, the 40 product will also contain some calcium sulfate, as will be the case when the nitrifying solution carries some calcium sulfate in suspension. The guanidine saltin this new composition may be that of any mineral acid but the phosphate and 45' sulfate are preferred.

T It will be seen, therefore, that this invention actually may be carried out by the modification of certain details without departing from its spirit or scope.

4. A fertilizer containing mono-calcium phos I claim: 1. A fertilizer containing calcium phosphate. phate and a guanidine salt. a'mmonium phosphate, and guanidine phosphate. 5. A superphosphate fertilizer containing as an 2. A fertilizer containing calcium phosphate, essential constituents. guandidine phosphate. 5 ammonium phosphate and a guanidine salt. 8. A superphowhate fertilizer containing as an 5 3. A fertilizer containing mono-calcium phosessential constituent a guanidine salt. phate and guanidine phosphate. HARRY A. CURTIS. 

